Shocker (CR 3)

Medium Outsider
Alignment: Usually neutral
Initiative: +4 (Dex); Senses: Listen +5 and Spot +5

AC: 14 (+4 Dex), touch 14, flat-footed 10
Hit Dice: 3d8+3 (16 hp); DR: 20/iron
Fort +4, Ref +7, Will +2
Speed: 5 ft., fly 30 ft. (perfect)
Space: 5 ft./5 ft.
Base Attack +3; Grapple -2
Attack: Touch +7 melee
Full Attack: Touch +7 melee
Damage: Touch 1d8 electricity
Special Attacks/Actions: Electricity
Abilities: Str 10, Dex 18, Con 13, Int 10, Wis 8, Cha 8
Special Qualities: Shocking discharge, immunities, fire resistance 10
Feats: Weapon Finesse (touch)
Skills: Hide +10, Listen +5, Move Silently +10, and Spot +5
Advancement: 4-6 HD (Medium-size); 7-9 HD (Large)
Climate/Terrain: Any land or underground
Organization: Solitary or swarm (2-11)
Treasure/Possessions: None

Source: Return to the Temple of Elemental Evil

Electricity (Ex): The touch attack of a shocker inflicts 1d6 points of electrical damage. This damage is dealt to the shocker as well.

Shocking Discharge (Ex): If touched with bare flesh (including being struck in combat with a fist or claw) or metallic weapon, the shocker delivers 1d8 points of damage the attacker. This is true whether or not the attack is capable affecting the shocker. The damage it inflicts is subtracted from the shocker's hit-point total as well.

Immunities (Ex): Shockers are immune to mind-influencing effects, poison, paralysis, stunning and disease. They're not subject to critical hits, subdual damage, ability damage, or energy drain.